If, like mine, all your feet have sheared off, you may be able to pry the center bit of plastic left in the lid at each foot out with tweezers. Obviously don't go digging deep or forcing things, but if you are lucky like I was then you don't need to remove all the screws and the lid. My new feet went in well and seem really well stuck. Make sure you clean the surface of the aluminium extremely well.

I didn't find any need to cut the plastic backing. I found that each foot easily came off the backing and I grabbed it with the tweezers.

I put a pencil mark on the lid showing the position of the little "key" nub and made a mark on the foot too, showing its position. This allowed me to align the "key" nub with it's hole easily.

Good instructions. Just remember to push the knife blade in right next to the aluminium case or you will damage the plastic surround. The obvious place to stick the blade in is not the correct spot! Look carefully.

My kit came with a new glass camera cover but I could have reused the old one. The glue would have held.

I used a heat gun to heat things a bit but I am well experienced as to what it too much heat.